中文摘要：

利用中国低纬度地区20个无线电探空站2008—2012年探空资料,分析大的敢水汽转换系数K值与地理位置间的关系,建立广西地区不需气象资料的K值模型。比较不同模型的精度、适用性,分析逐年增加样本数对预测精度的影响,探索如何更好地建立广西地区K值模型。结果表明：（1）在广西地区,Emardson模型总体的内、外符合精度与高程模型相当,Emardson模型与积分模型计算K值符合较好,总体内符合均方误差为0.0021,外符合均方误差为0.0018;（2）与高程模型相比,无需考虑高程因子的Emardson模型在广西地区适用性更强;（3）通过逐年增加样本数进行建模不能保证提高模型的预测精度,用最近的两年数据建模能够更好地预测第3年的K值。

英文摘要：

According to the 2008 -2012 sounding data of 20 radiosonde stations at the low- latitude of China , this paper analyzed the relationship between the Kvalue and location , built coef ficient K value model without meteorological data in Guangxi region. By comparing the accuracy and applicability of different models,the im-pact on prediction accuracy is analyzed by gradually increased samples year by year, and better ways of model-ing is found for the K value model in Guangxi. The results show that ： （ 1） Emardson model has the same inner precision and outer precision as the elevation model. Emardson is in good agreement with the integral method in calculating the K value. Emardson model＇s overall precision of inner coincidence MSE is 0. 002 1 , outer preci-sion MSE is 0. 001 8.（2） Without elevation factor , Emardson model has stronger appl icabi l i ty than the eleva-tion model. （ 3 ） It is not guaranteed to improve the prediction accuracy of the model by increasing the number of samples each year. With recent two years data, the value of K of the th ird year can be better predicted.